Improved furnace for galvanizing iron



W. BLAKE.

692 1 Gailvanizing'lronflodsz No. 1,6963 Patented Mar. 119, 1861.

Wifnesses:

Inventor:

AMT PHOTO-LITHO. C0. N.Y. [OSBORNEQ'S PROCESS.)

UNITED STATES, PATENT OFFICE.

WILLIAM BLAKE, or BosroN, MASSACHUSETTS.

IMPROVED FURNACE FQR GALVANIZING IRON.

Specification forming part of Letters Patent No. 31,696, dated March 19, 1861;

In'the use of the common zincing bath or trough employed in galvanizing tubes or rods or coating them with zinc there is a large loss of the metal by oxidation, as when zinc is in a melted state its affinity for oxygen is very great. My improved zincing bath or furnace is so constructed that but very small portions of the metallic contents are exposed to the at mosphere, and thus but little oxidation and loss of metal ensue in comparison to what result from the use of the open-trough bath.

In carrying out my invention I make the bath in the form of atube with an angular or curved bend, as seen at Lt in Fig. 4:, A being the tube. This tube I arrange so that its longer leg I) may be inclined to the horizontal plane in such manner that the two ends of the tube may be on or about on a level, as shown in the said drawings. Furthermore, the tube I support in bearings so applied to its longer leg I) as to enable it to be revolved on its axis in such manner as to cause the shorter leg 0 to turn from a Vertical down into a horizontal or an inclined position, such as will cause the tube to be emptied of any liquid contents, or the latter to fall out of it whenever the same may be necessary. The upper part of each arm of thetubular bath I make open, as seen at d and e-that is, not only so that melted zinc may bepoured into and out of the mouth or upper end, of the shorter leg, but an iron bar or a tube to be galvanized may be readily either introduced into or Withdrawn from the, longer leg. Under this tubular bath I place one or more furnaces B O for heating it, or I arrange the bath over one or more furnaces and Within their fines, and so that the heat may be passed either partially or wholly around the said tube, as occasion may require.

That part of the furnace which. may be against the side of the shorter arm should be so constructed as to allow of the revolution or turning of the tube or the movement of the said shorterarm from a vertical down into an inclined position, such as will suffice to dis charge the contents of the tube. To this end the furnace may be made with an opening or lateral passage 6, to be closed by a plate or door f, such opening being denoted :in Fig. 2 by dotted lines.

Instead of constructing the bent tubular bath in one entire piece and so that both legs I? 0 may be capable of being turned down, as

described, it may be made with the longer and inclined leg so fitted in the furnace as not to be capable of being revolved, in which case the shorter leg should be so applied to the longer leg as to be capable of being turned thereon or therein or from a vertical down into a horizontal or an inclined position, such as will enable the contents of the tube to be entirely discharged from it by gravity. Fur= thermore, the whole-tube may be stationary, and at its angle or bend it may be provided with a tapping hole or tube, through which the melted metal may be discharged as occasion may require.

In using this bath, after it may have been supplied with metal, the rods or tubes to be zinc-coated are to be introduced into th e longer arm of the tube, and after being suffered to remain there covered by the metal for a sufficient length of time they are to be Withdrawn endwise out of it. I As the tube is to be kept (generally speaking) nearly full of the metal, the extremities of the mass of the latter will be all of it which will be exposed to atmospheric action, and therefore but little oXida t-ion of the metal can take place.

I would remark that, although I have hereinabove described my tubular zinoing bath as made with its arms separate and having the shorter so applied to the longer as to be capable of being turned down with reference to the same, while such longer arm might remain stationary, I prefer to construct such bathof one entire tube, as by so doing I avoid leakage at the joint of the two arms. I also prefer to have the tube revolve in bearings applied to the furnace or arranged as described, and this rather than to have the tube stationary and provided with a discharging aperture or tube arranged at its angle or bend.

The nature or principle of my invention is to be found in the bent tube (open at its ends) arranged with respect to the horizontal plane, substantially as described, and provided with a ready means of being emptied or discharged of its contents.

I lay no claim to an ordinary open bath or trough arranged over and so as to be heated by one or more furnaces; but

What I do claim is My improved zincing bath as constructed of along bent tube (orits equivalent) arranged in one or more furnaces or heating-chambers and so as to operate substantially as described.

WM. BLAKE. Witnesses:

W. G. LEVI, F. P. HALE, Jr. 

